The high-stakes maneuvering over ownership of Fairview Health Services ended abruptly Wednesday, with Sanford Health and the University of Minnesota halting discussions about a merger or acquisition. The CEO of South Dakota-based Sanford, whose merger effort came under intense scrutiny the past two weeks, said Wednesday afternoon that he was ending discussions because Sanford has a policy of "only going where we are invited." Shortly thereafter, university President Eric Kaler said Fairview's board won't consider a proposal he made in January for the U to take over the hospital system. Instead, the two sides will talk about strengthening the existing arrangement in which Fairview has run the U's medical center since 1997.